A Discrete Vortex Method Investigation of Canonical Pitch Ramp-Hold Case

A Discrete Vortex Method code was developed in house to rapidly resolve the flow field over a thin airfoil for low Reynolds number unsteady aerodynamic applications. For the current investigation, the Fluid Dynamics Technical Committee Low Reynolds Number Working Group (FDTC-LRWG) canonical 45o linearly ramping pitch to hold case was analyzed. Parametric studies were performed to gage sensitivity to various parameters (such as angle of attack at which separation occurs, leading edge separation factor, and number of vortices) to the flow field generated. The FDTC-LRWG Pitch-Ramp-Hold Canonical cases executed by others in the group are used for the purpose of refining the accuracy of the code and are also used in an effort to define the bounds of applicability of this lower order method. After some tuning, the method ultimately proves to be quite versatile and accurate within the constraints of low Reynolds number unsteady flow fields to which is applied here